For the cost reduction of passivated emitter and rear cells (PERC), we propose a new rear contact formation method, in which an aluminum foil and an arc discharge system are used. The arc discharge system consists of inexpensive parts and does not contain any sophisticated part such as a laser ablation apparatus. Therefore, this system can save the cost of the rear contact forming process. We applied this technique to a test production of PERC. It is found that the arc discharge system can provide a similar performance to that attained by a conventional PERC production method.

A high power, tunable dye laser system composed of a master oscillator and power amplifiers is demonstrated. A single-mode cw dye laser oscillator of simple composition generates a narrow-bandwidth spectrum of less than 20 MHz compared with that of a pulse dye laser oscillator; however, the output power from the cw dye laser is low. Therefore, a high efficiency pre-amplifier for the pulse dye laser is needed. We developed a simulation code to amplify spontaneous emission and also designed a pulse dye laser amplifier to increase efficiency. In experiments, we obtained a power output pulse with a narrow-bandwidth spectrum with a very high power gain greater than 10,000 by using a four-pass pre-amplifier. Good agreement is obtained between the calculated and measured amplifier characteristics.

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